Tobacco product with flavorant



United States Patent i 3,402,721 TOBACCG PRODUCT WITH FLAVORANT Ernst T. Theimer, Rumson, John James Westbrook Ill, Shrewsbury, John Wolt, East Orange, and Alton Dewitt Quinn, Cranford, NJ., assignors to International Flavors & Fragrances, line, New York, N.Y., a corporation of New York No Drawing. Continuation-impart of application Ser. No. 519,952, Jan. 11, 1966. This application Nov. 9, 1966, Ser. No. 592,985

Claims. (Cl. 13117) This is a continuation-in-part of the Theimer, Westbrook, Wolt, and Quinn application Ser. No. 519,952, filed Jan. 11, 1966.

This invention has to do with a tobacco or tobaccolike product having improved smoking characteristics and processes for preparing such tobaccos, and more particularly, it relates to enhancing the flavor of tobacco-containing products, to novel tobacco products, and to certain novel compositions for use with tobacco.

The term tobacco as used in this specification and the appended claims means and includes, where the context permits, natural tobaccos such as burley, Turkish tobacco, Maryland tobacco, Virginia tobacco, and fluecured tobacco; tobacco-like products such as reconstituted tobacco or homogenized tobacco; and tobacco substitutes intended to replace natural tobacco such as various vegetable leaves, for example lettuce and cabbage leaves and the like.

There has been a marked trend in the tobacco industry toward the use of filters in cigarettes, cigars, and pipes. In addition, applications have been found for reconstituted or homogenized tobaccos and for synthetic wrappers and fillers as substitutes for natural tobacco. Such smoking products have suifered from poor flavor characteristics. They are generally regarded as harsh, as containing undesirable aroma quality, and otherwise are considered as having poorer smoking flavor and less pleasant smoking character. These innovations have accented the need for improving the flavor of tobacco products and otherwise enhancing the smoking characteristics of these products. Oftentimes improved flavor may be obtained by the use of higher grade tobacco leaf. However, this is costly, the supply of certain types of leaf has been limited, and there has accordingly been increased use of tobacco stems and poorer grades of tobacco in various blends combined with the more costly ingredients.

It has been suggested that various additives or flavoring agents be incorporated with, or added to, tobacco products to improve their flavor. These additives and agents have not been uniformly successful because they have suffered from a number of disadvantages. The main disadvantages of the additives and agents previously proposed for this purpose have been their relative unavailability, and high cost, and inadequate aroma and flavor.

Accordingly, this invention provides an improvement in the flavor and smoking characteristics of tobacco products and provides products therefor.

Further and more specific objects, features, and advantages will clearly appear from the detailed description given below.

The invention comprises the novel products, the specific embodiments of which are described hereinafter by way of example and in accordance with which it is now preferred to practice the invention.

In accordance with this invention it has been found that tobacco materials can be improved in flavor and smoking characteristics by incorporating in, or adding to, such materials a small but eflFective amount of one or more novel lactic acid esters of an isoprenoid alcohol or alcohols. Lactic acid esters of such isoprenoid alcohols are produced by novel processes. Tobacco or tobacco-like products containing a lactic acid ester of one or more of the aforesaid alcohols, or mixtures of such esters, are milder and less harsh and have a pronounced tobacco taste and character. This improved taste, character, and flavor is noted even when the tobacco is smoked through a filter.

The lactic acid esters of the isoprenoid alcohols of this invention have been found to possess a combination of properties which makes them particularly suitable as tobacco flavoring agents in that such compositions are effective at low concentrations and thus will not bleed into tobacco wrapping materials, are low in cost, are stable on prolonged storage, are not known to decompose on smoking to give materials which are physiologically harmful, and their flavor enhancement is effective even through a filter. The use of the lactic acid esters of the isoprenoid alcohols of this invention as tobacco flavoring agents also permits greater flexibility in utilizing new blends of tobacco.

The tobacco flavoring agents of this invention are lactic acid esters of isoprenoid alcohols, said alcohols being represented by the following formula:

wherein n is an integer of 2 or more; the dotted lines mean that the bond at the positions indicated is either a single or a double bond, one double bond being present in each isoprene unit, except those containing a tertiary hydroxyl; and k is 1 or 2, the value of k being determined by the position of the double bond. The alcohol molecule contains at least one hydroxyl and can contain several hydroxyls, so that m is at least one. The wavy line indicates that the hydroxyl(s) can be terminal or substituent of the chain. It will be understood that in molecules containing no primary allylic hydroxyl the terminal group will be a conjugated dienoic system or a cyclic, e.g. methenyl, system.

The alcohols used in the preparation of the esters of this invention can either be naturally occurring materials, such as the terpene and sesquiterpene alcohols, or they can be materials prepared by the polymerization of iso prene as hereinafter more fully disclosed. The terpene alcohols which can be used include nerol, geraniol, and terpineol. The sesquiterpene alcohols include farnesol and nerolidol. Exemplary isoprenoid alcohols prepared by the polymerization of isoprene include 2,6,10,14-tetramethyl-2,6,10,14-hexadecatetraene 16-01; 16-(1-methyl- 4 isopropenyl cyclohexyl) 2,6,10,14 tetramethyl- 2,10,14 hexadecatetriene-6-ol; 2,6,10,14 tetramethyl- 6,10,13,15 hexadecatetraene 2 ol; 2,6,10,14,18,22,26- heptamethyl 2,6,10,14,18,22,26 octacosaheptaene-28- ol; 2,10,18,26-tetramethyl-6,l4,22 trimethylene-2,25,27- octocosatriene 10,18 diol; 2,6,10,14,18,22,26,30,34 nonamethyl 2,6,10,14,l8,22,26,30,34 hexatriacontanonaen 36 ol; 2,6,10,14,18,22,2630,34,38,42,46-octatetracontadodecaen 48 01; and 2,6,10,14 tetramethyl- 1,10,l4-hexadecatriene-6,16-diol. It should be understood that the isoprenoid alcohol precursors represented by the above formula can include additional hydroxy groups in the chain or can have other tertiary hydroxy groups, and such materials are considered equivalent for purposes of this invention.

The IR, UV, and nuclear magnetic resonance data on alcohols prepared by isoprene polymerization show the presence of vinylidene methylene groups, tri-substituted double bonds, primary allylic hydroxyls, and tertiary hydroxyls, and are suggestive of groups such as terminal menthenyls. It will be understood that mixtures of one or more of the terpene, the sesquiterpene, or the polyisoprenoid alcohol esters can be used in combination and certain combinations are preferred as hereinafter disclosed. It will accordingly be understood that the formula given as representative of the isoprenoid alcohols contemplates and includes all of the variations and mixtures thereof herein set forth.

It is desirable that n in the foregoing formula be at least two. Very high molecular weight isoprenoid alcohols can be used in producing the esters of this invention, but for ease of handling and processing, it is desirable that very high molecular weight materials be excluded, and it is accordingly preferred that n in the above formula be an integer from about 2 to about 15, inclusive.

To produce the lactate esters the foregoing alcohols are esterified with lactic acid, the acid desirably being present in quantities at least equimolar with the isoprenoid alcohols. For the majority of uses, it is preferred that the lactic acid be esterified with the isoprenoid alcohol or alcohols in a proportion of from about 3 to about 25 equivalents of lactic acid for each molecule of isoprenoid alcohol. It is believed that the isoprenoid lactate esters of this invention are generally polylactates, that is, that the carboxylic acid group of a lactic acid molecule forms an ester with the hydroxyl group of a lactic acid molecule which is esterified with an isoprenoid hydroxyl group. The free lactic hydroxyl group can in turn be esterified with another lactic carboxylic group, and so on. Molecular ratios of lactic acid to isoprenoid alcohol in the range of from about 6 to about 18 give superior taste improvement in tobacco, and ratios of about 9 are preferred because such ratio is optimum for many tobacco mixtures.

The isoprenoid lactate esters of this invention can have acid contents of from nil to about 0.045, alcohol contents from about 0.4 to about 2.5, and ester contents of from about 0.3 to about 7.5. All acid, alcohol, and ester contents are expressed herein in milliequivalents of reagent per gram of sample, as determined by standard analytical methods. While certain IR ranges in the lactates are obscured, for alcohols prepared from isoprene the 240 millimicron UV absorption indicates 0.2- 0.3 moles dienoic material per mole of alcohol (based on a molecular weight of 550-600 for the alcohol).

Briefly, the process for the preparation of isoprenoid lactate esters by isoprene polymerization involves the reaction of isoprene and a carboxylic acid to form the isoprenoid alcohol carboxylic acid esters and the reaction of the carboxylate so formed with a suitable lactic acid material to form the isoprenoid alcohol lactate. Generally it is necessary to purify the material during at least one step of the process so as to obtain the desired chain length in the isoprenoid material. When terpene and sesquiterpene alcohols are used, they are similarly esterified with suitable lactic acid material to form the isoprenoid alcohol lactate. It is frequently helpful to separate the lactic esters into different fractions depending upon their ultimate use, as further disclosed hereinafter.

A wide variety of'steps and sequences of steps can be used in practicing the process. The isoprene is polymerized at low pH in the presence of a carboxylic acid. The isoprenoid ester so formed can then be separated into the desired fractions before reaction to form the lactate or the unseparated polymer can be reacted directly with a lactate material to form the esters by transesterification. If the fractions are separated, the desired fraction can be saponified to produce the free alcohol and then reacted with lactic acid or a lactate to produce the isoprenoid alcohol lactate of this invention. Alternatively, the entire mass of polymerized isoprene can be saponified to form the alcohol and the alcohol can be purified and reacted with lactic acid or lactate to form the isoprenoid alcohol lactate or the alcohol can be reacted with the lactic acid or lactate to form esters and then the esters purified or separated as desired. Certain desirable processes for the practice of this invention are 4 disclosed below and embodiments thereof described in the examples.

The first step in the process when isoprene is the starting material is the preparation of the isoprenoid alcohol material. The isoprenoid alcohol or alcohols from which the lactic acid ester flavoring agents of this invention are derived are preferably obtained from the controlled polymerization of isoprene in a lower aliphatic carboxylic acid. In general, the controlled polymerization of isoprene is of the ionic type, and is preferably carried out by reacting isoprene in a lower aliphatic carboxylic acid and in the presence of a strong acid catalyst, preferably at a pH of 3 or less, under controlled temperatures for a period sufiicient to obtain the desired number of isoprene units in the polymer. Any lower alpihatic carboxylic acid can be used, although saturated lower alkyl monocar- 'boxylic acids such as acetic acid, propionic acid, and the like are preferred. The strong acid catalyst can be a mineral acid such as sulfuric or phosphoric acid, acidic resins such as sulfonated polystyrene resins like Amberlyst 15 made and sold by Rohm & Haas Company, or other strong acid equivalents.

The temperature and duration of the reaction depend on a variety of factors including the economics of reaction time and conversions desired and the specific organic acid and catalyst employed. At low temperatures the reaction time becomes excessive, while at temperatures much above 70 C. the reaction may proceed too quickly, higher polymers of isoprene may be formed, and a closed system and superatmospheric pressure are required to prevent loss of the volatile isoprene. Generally, the reaction temperature can vary from about 15 C. to 70 C., and temperatures of from about 25 C. to 35 C. are preferred. Depending upon the temperatures chosen, the time of the reaction can vary from about 5 to 200 hours, and preferably the reaction period is from about 50 to about hours.

When the reaction is completed, the acid catalyst is neutralized by the addition of a basic material or removed from the reaction mixture, and the unreacted materials and the reaction products containing less than two isoprene units per molecule can be separated by any conventional method. Preferably, such products are separated by distillation, and vacuum distillation is desirable. The residue from this separation containing products of two and more isoprene units per molecule can further be refined by high vacuum distillation, and short path thin fih'n, or molecular, distillation is preferred. The distillate obtained from the molecular distillation contains isoprenoid lower alkyl esters which are then used to produce the polyisoprenoid alcohol-s used in practicing this invention or are transesterified with a desired lactate material.

The terpene and sesquiterpene alcohols can be pure, commercially pure, or mixtures of various terpene alcohols. The terpene alcohols can be admixed with the alcohols prepared from isoprene prior to esterification with the lactic acid material, or the terpene alcohol lactate and isoprene-derived alcohols lactate can be admixed. Desirable esters have been made from a mixture of geraniol and nerol in various proportions, and other blends are also desirable depending on the type of tobacco, as further disclosed hereinafter.

Preparation of the lactic acid esters of isoprenoid alcohols can be accomplished by any of the conventional techniques including transesterification with an alkyl lactate, preferably a lower alkyl lactate, at elevated temperatures in the presence of a solvent, preferably a hydrocarbon solvent, and a basic material such as' an alkali-metal alcoholate; saponification of the isoprenoid ester to the alcohol followed by direct esterification of lactic acid with the isoprenoid alcohols at elevated temperature in the presence of a dehydrating agent such as concentrated sulfuric acid; or transor crossesterification of the isoprenoid alcohol with a lower alkyl lactate, e.g. ethyl lactate or butyl lactate, in an inert solvent preferably an aromatic hydrocarbon, for example, benzene, toluene or the like, and in the presence of a basic material such as an alkali-metal alcoholate or the like.

The temperature of the reaction will depend upon the type of esterification procedure and the pressure used. The pressure can be atmospheric or subor superatmospheric. When normal atmospheric pressures are used, the preferred temperature for the esterification ranges from about 70 C. to about 125 C. The esters can be purified by simple distillation of the volatiles, and the ester recovered from the residue by distillation, preferably short path, thin film, high vacuum distillation. Preparation of the lactic acid esters of isoprenoid alcohols by transesterification is preferred, for in this way undesirable side reactions are minimized. For example, by the transesterification method of preparing the esters, polymerization of lactic acid can be controlled and dehydration of the isoprenoid alcohols is minimized.

The particular isoprenoid lactic acid ester or esters of this invention are selected according to the type of smoking and sidestream character desired, the type of tobacco being utilized, the type of product to be improved (e.g., regular or filter cigarettes, cigars, or pipe tobacco), the processing method and conditions, and the particular character of product desired. The term sidestrearn as used herein means the smoke resulting directly from burning the tobacco in distinction from the flavor and aroma obtained by drawing smoke through the tobacco.

Asis known, different tobaccos have different characteristics depending on the type of tobacco, the variety of tobacco, the type of soil on which it is grown, the types and amounts of fertilizer and micronutrients used, the weather conditions during the growing season, the part of the leaf or plant which is incorporated, and subsequent treatment of the leaf after it is severed from the plant. For illustration, some tobaccos have foreign flavors and aromas such as earth, acrid, or paper-like when they are smoked. Illustrative of tobaccos with such foreign notes are black tobaccos; stems; reconstituted tobacco sheet; Argentine, Mexican, and other tobaccos produced in South and Central America, Africa, and Asia; and the like. On the other hand some low-grade tobaccos have little or no flavor at all. These low-grade tobaccos are relatively flavorless due to the growing conditions, the variety of plant, the stalk position of the leaf, or certain curing operations. Still other tobaccos are harsh, and have a strong impact on the throat. Generally these harsh tobaccos are those with a high alkaloid, or high total volatile base, content such as is formed in some burleys and in tobaccos grown in soil containing large quantities of available nitrogen.

The isoprenoid lactates produced according to this invention can, as described above, be separated into different fractions, as for example by distillation, or the entire range of lactates produced can be utilized. For example,

the lactates can be separated into a large number of fractions which can be used singly or in combination to provide the desired smoking and sidestream characteristics in the tobacco. With many tobaccos, the smoking and sidestream characteristics can be improved by utilizing a range of lactates.

It has been found that the lower boiling lactates are particularly useful in improving the organoleptic characteristics of foreign-flavored tobaccos. The higher boiling lactates are particularly useful in improving low-grade or harsh tobaccos. Accordingly, while the entire range of lactates formed can be used to improve the flavor and aroma characteristics of tobaccos, especially the foreignflavored tobaccos, in many instances it is preferred to separate the lactates into lowand high-boiling sections and to utilize the low boilers on foreign-flavored tobaccos and the high boilers on low-grade or harsh tobaccos. When a spinning disc molecular still having a rotor diameter of about five inches (such as the CMS-S centrifugal molecular still made by Consolidated Vacuum Corporation, Rochester, NY.) is used at a pass rate of 25 gm./min., it is preferred to use the lactates obtained at rotor temperatures below about C. for foreignflavored tobaccos and the lactates obtained at rotor temperatures above about 75 C. for low-grade tobaccos.

It has further been found that the lactic acid esters of two or more types of the alcohols of this invention can be combined to obtain flavoring agents which have advantages in some instances over the flavoring agents prepared from single types of alcohol. For example, it has been found desirable with certain types of tobacco to combine the lactic acid esters of a mixture of nerol and geraniol or other alcohols where n in the above formula is 2 to act as an enhancer with the lactic acid esters of isoprenoid alcohol prepared from isoperene polymerization and having values of 11 greater than 2. In such instances the combination of the terpene alcohol lactates and isoprenoid alcohol lactates obtained by isoprene polymerization is found to retain much of the character of the latter and to make the latter more readily distributed throughout the tobacco to be treated.

Certain lactic acid polymers also possess the characteristic of acting as an enhancer for the isoprenoid alcohol lactates. While the lactic acid polymers possess some flavoring effect of their own, this effect is greatly potentiated by combination with lactates of the isoprenoid alcohols, and particularly with the lactates of isoprenoid alcohols prepared by isoprene polymerization. Such lactic acid polymers are those containing two or more ester groups per molecule. They can conveniently be prepared by reacting the lactic acid hydroxyl group with the lactic acid carboxylic group or by causing lactic acid esters to undergo intermolecular self-alcoholysis.

Lactic acid polymers for use in the practice of this invention can be obtained directly from lactic acid by heating the acid to remove water. Such water removal is preferably augmented by conducting the reaction under reduced pressure or in the presence of entraining agents which can be aromatic or substituted aromatic hydrocarbons such as benzene, toluene and the like or chlorinated hydrocarbons, especially chlorinated lower aliphatic hydrocarbons such as tetrachlorethylene, trichlorethane, carbon tetrachloride, ethylene dichloride, propylene dichloride, methylene chloride, butyl chloride and the like. This reaction produces lactic acid polymers together with di-lactide, the heterocyclic dimer.

The heating is carried out at a temperature which accelerates the vaporization of any water present as an impurity or resulting from the polymerization. Thus, the temperature at which the reaction is performed can vary over a wide range depending upon whether reduced pressure is utilized and the particular entraining agent, if any, which is used. Accordingly, the process is desirably carried out at temperatures from about 70 C. to about C. The pressure at which the reaction is carried out can be atmospheric or subor super-atmospheric, although atmospheric and subatmospheric pressures are preferred.

The process can, if desired, be carried out with a catalyst to accelerate the reaction. Generally, it has been found that small quantities of relatively acidic materials are well suited for use as catalysts in the polymerization of lactic acid. Suitable catalysts, for example, include sulfuric, hydrochloric, phosphoric, toluene sulphonic acids and the like.

The degree of polymerization of the lactic acid is conveniently controlled by observing the quantity of water removed from the reaction mixture. Generally, longer reaction times and higher temperatures result in the formation of higher polymers and the consequent withdrawal of larger quantities of water than is the case with the lower polymers. The preferred lactic acid polymers for use in this invention are materials containing from two to about ten lactic acid units.

When the lactic acid polymers are obtained by intermolecular self-alcoholysis the lower alcohol esters of lactic acid are preferred. Since the reaction is controlled according to the removal of the free alcohol formed during the self-alcoholysis, lower aliphatic alcohols containing from about one to about four carbon atoms are desirable, and the ethanol esters are especially preferred because of the relatively high volatility and safety of ethanol.

The lactic acid polymer is obtained from the ester of lactic acid by heating the ester, preferably in the presence of a catalyst, with the simultaneous removal of alcohol formed during the reaction. The use of a catalyst is preferred to increase the velocity of the reaction, and the catalyst can be an acidic or basic esterification or alcoholysis catalyst. For example, acidic catalysts such as sulfuric, hydrochloric, phosphoric, and toluene sulfonic acids; sulfur dioxide; 'boric anhydride; boron trifluoride; aluminum ethylate; magnesium methylate; other alcoholates of metals such as sodium, magnesium, aluminum, and the like; acidic salts such as aluminum chloride, ferric chloride, and copper sulfate; acidic ion exchange resins such as the modified phenol-formaldehyde sulfonic acid type and the like can be used in preparing the esters by intermolecular self-alcoholysis.

As discussed above, the molecular Weight of the lactic acid polymers formed depends upon the time and temperature of the self-alcoholysis reaction and is indicated by the amount of alcohol removed from the reaction mixture. This method of preparing polylactic acid esters can be carried out at atmospheric or subor superatmospheric pressures, and as disclosed above the use of atmospheric or subatmospheric pressures is preferred.

When the lactic polymers are prepared from lactic acid esters as described above, it will be understood that the reaction product is an ester of the polylactic acid. Thus, when the process is carried out with ethyl lactate, the reaction product comprises ethyl lactyl lactate and higher ethyl esters of polylactic acids such as ethyltrilactate, ethyltetralactate, ethylpentalactate and the like.

After the polymerization of the lactic acid or lactic ester has been carried out as described above, the condensation product so prepared can be recovered from the reaction mixture by any convenient method. For example, the polymers can be recovered from the reaction mixture by distillation such as fractional or molecular distillation or by extraction techniques with solvents. The use of distillation techniques permits the separation of the polymers into various fractions, and in some instances as more fully described below, the use of certain fractions may be preferred in connection with a particular isoprenoid alcohol lactate used and the type of tobacco upon which the ultimate flavoring material is to be utilized.

Accordingly, in certain preferred embodiments of this invention polymers of lactic acid can be prepared and used by themselves or preferably in combination with the lactates of isoprenoid alcohols to act as flavoring agents. Where a combination of lactates of various isoprenoid alcohols is to be used, as disclosed herein, the lactates themselves can be admixed or the desired mixture of alcohols can be prepared and then esterified to produce the mixture of terpene and sesquiterpene and/or polyisoprenoid alcohols. A combination of these methods can also be used.

The amounts of each of the two or more components can be varied over a wide range. In the case of enhancers which are also flavoring agents, such as the lactate of igeraniol, the amount of the geraniol lactate in admixture with the longer chain isoprenoid alcohol lactate from isoprene polymerization can vary up to 100%. However, where enhancers are used, it is preferred to use from about 50% to about 80% in admixture with such longer chain isoprenoid alcohol lactate. Generally, when terpene or sesquiterpene alcohol lactates are used as enhancers with longer chain isoprenoid alcohol lactate it is preferred to use from about 60% to about 80% enhancer, and when lactic acid polymer is utilized as active vehicle in combination with longer isoprenoid alcohol lactate it is preferred to use from 50% to about enhancers.

The flavoring agents of this invention can be applied directly to the tobacco or otherwise incorporated into the finished product. As examples, the lactates can be used to treat the paper wrappers for cigarettes or the tobacco leaf wrapper for cigars. It is desirable to add the lactates directly to the tobacco itself. The lactates can be added directly to the tobaccos as-is and they are preferably added with a vehicle in the form of solutions, suspensions, emulsions, and the like since the preferred usage levels are relatively low and the amount added is more easily controlled and evenly distributed when vehicles are used. For example, the lactates of this invention can be added by spraying the leaf with a solution, preferably an alcoholic solution, of the lactate; the lactates can be added directly to the slurry from which reconstituted tobacco leaf is prepared; they can be added to tobacco stems and the like by spraying; they can be incorporated into the casing (the aqueous mixture of additives applied to blended leaf prior to cutting); they can be incorporated in top flavors (the materials added to the cut leaf after drying) and the like.

The lactic acid ester flavoring agent can be incorporated with the tobacco before or after blending a number of tobacco varieties, or the flavoring agent can be added to one or more of such tobacco varieties prior to blending. The agent can be added prior to or after aging the tobacco. The amount of the tobacco flavoring agent composition used depends upon a number of factors including the particular flavor or smoking character desired, the particular tobaccos used, the type of product, and the specific flavor agent composition employed.

Generally, the flavoring agent mixture of this invention is admixed with tobacco or tobacco-like materials in amounts of from about 0.05 to 5.0 percent by weight based on the weight of the tobacco materials at their finished mixture content. At proportions below about 0.05 percent little improvement is detected, and at proportions much above about 2 percent non-tobacco characteristics or objectionable flavors or aromas may be produced. Where low-grade tobaccos are treated with the flavoring agents of this invention, up to 5 percent of the agent can be present in the tobacco. These high levels are used chiefly in heavily-cased pipe tobaccos. The preferred usage level is from about 0.20 to about 1.0 percent. Where foreign-flavored tobaccos are treated, from about 0.50 to about 2.0 percent of the agent of this invention is preferred.

The tobacco flavoring agent compositions of this invention can also be combined with other flavor or aromaenhancing materials to obtain various pleasing combinations of quailities. These can be formulated as desired to obtain the particular flavor and aroma nuances required. Other smoke enhancing ingredients with which the compositions of this invention can be combined include essential oils, balsam, fruit flavors such as peach, walnut, and cherry, coriander, coumarin, lactic acid, and phenylacetic acid. Other nuances such as spice, nut, fruit, rum, honey, and the like can be added to the compositions of this invention or used in conjunction therewith.

The following examples are (given to illustrate preferred embodiments of the invention as it is now preferred to practice it. It will be understood that these examples are illustrative. The invention is not to be considered as restricted thereto except as indicated in the appended claims.

EXAMPLE I Preparation of isoprenoid alcohol acetate To a flask fitted with reflux condenser, stirrer and thermometer 3000 gm. of isoprene, 3000 gm. of glacial acetic acid, 15 gm. of water, 7 gm. of hydroquinone, and 10 gm. of concentrated sulfuric acid are charged. The mixture is stirred for six hours to form polymers of iso- 9 prene and then allowed to stand at about 25 C. for 120 hours with stirring for 30 minutes after each 24-hour period.

The catalyst is then neutralized by adding 50 gm. of anhydrous sodium acetate to the mixture, and the mixture is stirred for 30 minutes. The reflux condenser is replaced with a distillation head and the reaction mixture is heated to 50 C. A fraction weighing 703 gms. is obtained. This fraction is essentially pure isoprene.

The pressure is reduced to 100 mm. Hg and the temperature of the reaction mixture is held at 50 C., and a fraction weighing 545 gms. is obtained. This mixture consists of 235 gms. (43%) of acetic acid and 310 gms. (57%) of isoprene.

The pressure is reduced to 3 mm. Hg and the temperature of the reaction mixture is held at 50 C. A fraction weighing 2,462 gms. is obtained. This fraction consists of 2,157 gms. (87.6%) of acetic acid and 305 gms. (12.4%) of phenyl acetate.

The pressure is held at 3 mm. Hg and the temperature of the reaction mixture slowly raised to 200 C. A fraction weighing 942 gms. is obtained. The residue weighs 256 gms.

The residue comprises a mixture of C to C isoprenoid hydrocarbons and a mixture of C to C isoprenoid acetates, in which the acetate portion of the mixture represents about 70 percent by weight.

EXAMPLE II Preparation of isoprenoid alcohol To a solution of 1600 gms. of potassium hydroxide in 6280 gms. methanol is added at reflux 5000 gms. of the residue containing isoprenoid acetate made as in Example I (acid content: 0.015, ester content: 1.l9, alcohol content: 0.104). The mixture is refluxed for an additional four hours, cooled to room temperature, neutralized with 1900 ml. of concentrated hydrochloric acid, and washed twice with 8 liters of a 5% sodium chloride solution, the product being subsequently extracted with liters of petroleum ether, dried over magnesium sulfate and filtered. The petroleum ether is recovered under vacuum. Crude material in the amount of 4571 gms. is obtained (acid content: 0.06, ester content: 0.06, alcohol content: 0.95). The crude is then molecularly distilled. About '3548 gms. of material containing about 70% C -C isoprenoid alcohols, and 30% C -C isoprenoid hydrocarbons is obtained.

The alcohol of Example II shows IR absorption at 10.0 indicating about /3 mole of primary allylic hydroxyl per mole of alcohol (based on a molecular weight of 550-600) and 8.6-8.9;1. absorption indicating tertiary hydroxyls. This alcohol shows UV absorption at 240 and 280 my, the 240 m absorption indicating about 0.2-0.3 mole of conjugated dienoic material per mole based on above molecular weight.

EXAMPLE III Preparation of lactice acid ester of isoprenoid alcohol A mixture of 97-1 gms. of isoprenoid alcohol made in accordance with the procedure of Example II, 101 gms. of ethyl lactate, -10 gms. of sodium methylate, and 2000 gms. of toluene are heated and the methanol/ethanoltoluene azeotropes are distilled off for a period of 8 hours. The reaction mass is then cooled, acidified with acetic acid, and washed to neutrality with water and dilute sodium bicarbonate solution. The toluene is recovered under vacuum. About 976 gms. of crude reaction product is obtained and 480 gms. of this crude product is washed three times with water and dried to obtain the lactic acid ester of isoprenoid alcohol (acid content: 0.01, ester content: 0.38, alcohol content: 0.86). Another 480 gms. of the crude product is molecularly distilled to obtain the fract1ons listed below at the temperatures and pressures shown:

Fraction number Rotor temperature Vacuum, microns g) (Hg) 56 55 05 33 66 2s 68 23 09 18 73 16 a0 10 84 14 90 14 102 13 103 12 100 12 11s 12 120 12 15 A total of 413 gms. of material is obtained. The indicated fractions test as follows:

Fraction number Acid content Ester content Alcohol content EXAMPLE IV Preparation of lactic acid ester of isoprenoid alcohol A mixture of 971 gms. of isoprenoid alcohol made in accordance with the procedure of Example II, 303 gms. ethyl lactate, gms. sodium methylate, and 2000 gms. toluene is heated and the methanol/ethanol-toluene azeotropes are distilled 01f during a period of 9 hours. The reaction mass is then worked up as in Example III and 1085 gms. of crude is obtained. About 500 gms. of the crude is washed three times with water and dried to obtain the lactic acid ester of isoprenoid alcohols (acid content: 0.01, ester content: 118, alcohol content: 0.83). Another 500 gms. of the crude reaction product is molecularly distilled under reduced pressure to obtain the fractions indicated below at the temperatures and pressures shown:

Fraction number Rotor temperature Vacuum, microns (fl e) A total of 432 gms. of material is obtained. The indicated fractions test as follows:

55 Fraction number Acid content Ester content Alcohol content EXAMPLE V Preparation of lactic acid ester 65 of isoprenoid alcohol Fraction number Rotor temperature Vacuum, microns 58 65 70 50 73 30 7e 30 7s 22 e2 19 30 10 94 14 A total of 504.5 gms. of material is obtained. The indicated fractions test as follows:

Fraction number Acid content Ester content Alcohol content 006 a. 13 1. 05 007 2. 02 64 006 1.80 75 005 1. s2 84 .006 2. 14 86 011 2. a 9s 020 2. 22 .81

EXAMPLE VI Preparation of lactic acid ester of isoprenoid alcohol A mixture of 303 gms. of lactic acid, 150 gms. of benzene and 4.4 gms. of concentrated sulfuric acid is refluxed using a Bidwell trap, and the aqueous layer is withdrawn until liberation of water ceases. Then 408 gms. of isoprenoid alcohol made in accordance with the procedure of Example II is added and the reaction mass further refluxed with water removal, until liberation of water again ceases. The mass is washed to neutrality with water and dilute sodium bicarbonate solution to obtain 392 gms. of crude lactic acid esters of isoprenoid alcohol. About 380 gms. is molecularly distilled under reduced pressure and the fractions noted are obtained at the temperatures and pressures shown:

Fraction number Rotor temperature Vacuum, microns deg) A total of 259 gms. of material is obtained. The indicated fractions test as follows:

Fraction number Acid content Ester content Alcohol content EXAMPLE VII Tobacco flavor enhancing A series of tobacco blends is prepared by spraying a solution of each of the agents shown in the following tabulation in equal parts by weight of acetone and denatured ethyl alcohol onto a tobacco blend consisting of 55% by weight of Type 12 Virginia tobacco and 45% by weight of burley tobacco. The agent is applied to the tobacco blend at a level of 1% by weight based on the weight of tobacco. Each of the sprayed tobacco blends is air dried, made into cigarettes, and conditioned by holding overnight. The cigarettes are evaluated by organoleptic testing wherein they are smoked by a test panel and their smoking characteristics determined by sensory methods.

taste'mild smooth. Fraction 3 of Example VI Smoother improved flavor. Lactate ester of isoprenoid alcohols of Example VI Smoother, milder taste.

EXAMPLE VIII In accordance with the procedure described in Example VII, comparison tests are made among cigarettes made from a control (untreated), a sample treated with 1% by weight of a mixture of 40% lactic acid and isoprenoid alcohol, and a sample treated with 1% by weight of fraction 14 of the lactate ester of isoprenoid alcohol of Example V. The tobacco used in the test cigarettes is a 45-55 blend of burley and Virginia tobaccos.

The test smokers reject the samples treated with the lactic acid-isoprenoid alcohol mixture as having a floral-- perfumy-alien taste. Cigarettes made from tobacco treated with the lactate ester fraction of isoprenoid alcohols are preferred over the control.

EXAMPLE 1X Using the techniques described in Example VII, a comparison is made among cigarettes made from untreated tobacco (control), tobaccos treated with fraction 14 of the lactic acid ester of isoprenoid alcohol of Example V, and tobaccos treated with lactic acid. In each case 1% by weight of the flavoring agent is added to a 44-55 blend of burley and Virginia tobaccos. Although the lactic acid-treated tobaccos smoke smoother than the control, no enhancement in flavor over the control is detected. The cigarettes made from tobaccos treated with the lactic acid esters of isoprenoid alcohols not only are found to smoke smoother than the control but the esters also retain and enhance the flavor of the cigarette.

' EXAMPLE X Application in small amounts by weight of the lactic acid esters of isoprenoid alcohols to tobacco products utilizing cigar stems and various tobacco substitutes upon organoleptic testing is found to reduce the otherwise harsh, acrid, woody taste of such tobacco products.

EXAMPLE XI Preparation and evaluation of lactate esters of isoprenoid alcohols A mixture of 242.7 gms. saponified isoprenoid actate residue (acid content: nil, ester content: 0.025, alcohol content: 1.03), 75.7 gms.-ethyl lactate, 7.5 gms. sodium methylate and 500 gms. toluene is heated and the methanol/ethanol-toluene azeotropes are distilled off over a period of 3% hours. The reaction mass is then cooled, acidified with acetic acid, and washed to neutrality with water and dilute sodium bicarbonate solution. The toluene is recovered under vacuum. About 253 gms. of crude is obtained (acid content: 0.002, ester content: 1.40, alcohol content: 0.88). About 245 gms. of crude is distilled under reduced pressure and 180.6 gms. is obtained. The fractions obtained at the indicated rotor temperatures on the molecular still test as shown below:

Fraction Acid Ester Alcohol Rotor Vacuum, number content content content temp. microns 13 Fractions 1-6 are combined (-86.9 gms.; acid content: 0.003, ester content: 0.44, alcohol content: 0.73) and fractions 7-12 are combined (93.7 gms., acid content: 0.007, ester content: 1.28, alcohol content: 1.01).

The foregoing material is representative of esters obtained by reacting a 4 ratio of moles of alcohol to equivalents of lactic acid. The low-boiling section is found to improve the taste and sidestream odor of stems, black tobacco, and reconstituted tobacco sheet. The high-boiling section tends to smooth out the harshness of heavy, harsh cigarette tobaccos and gives more body and an enhanced flavor to low-grade and mild tobaccos.

EXAMPLE XIII A mixture of 242.7 gms. of the saponified isoprenoid acetate residue of Example XI, 227.2 gms. ethyl lactate, 22.5 gms. sodium methylate, and 1250 gms. toluene is heated, and the methanol/ethanol-toluene azeotropes are distilled off over a period of 3% hours. The reaction mass is then cooled, acidified with acetic acid, and Washed to neutrality with Water and dilute sodium bicarbonate solution. The toluene is removed under vacuum. About 286 gms. of crude is obtained (acid content: 0.004, ester content: 2.87, alcohol content: 1.10), and 276 gms. of crude is distilled under reduced pressure, and 215.5 gms. of product is obtained. The fractions obtained at the indicated rotor temperatures test as shown below:

Fraction Acid Ester Alcohol Rotor Vacuum, number content content content temp. microns Fractions 1-4 are combined (95.5 gms., acid content: 0.006, ester content: 2.05, alcohol content: 1.05) and fractions -11 are combined (120.0 gms., acid content: 0.01, ester content: 2.27, alcohol content: 1.20). This lactate shows UV absorption characteristics similar to those of Example H.

The foregoing material is representative of esters obtained by reacting a 1/9 ratio of moles of alcohol to equivalents of lactic acid. The low boiling section is found to be excellent in improving the taste and sidestream odor of stems, black tobacco, and reconstituted tobacco sheet. The high-boiling section is found to be excellent in smoothing out the harshness of heavy, harsh cigarette tobaccos and in enhancing the flavor of mild and low-grade tobaccos.

EXAMPLE XHI A mixture of 242.7 gms. of saponified isoprenoid acetate residue of Example XI, 454.4 gms. ethyl lactate, 45.0 gms. sodium methylate and 2500 gms. toluene is heated and the methanol/ethanol-toluene azeotropes distilled off over a period of 8 /2 hours. The reaction mass is then cooled, acidified with acetic acid, and washed neutral with water and dilute sodium bicarbonate. The toluene is recovered under vacuum. About 373 gms. of crude is obtained (acid content: 0.009, ester content: 4.74, alcohol content: 1.39), 363 gms. of crude is distilled under reduced pressure, and 279.5 gms. of product is obtained. The fractions obtained at the indicated rotor temperatures test as shown below:

Fractions 1-6 are combined (135.0 gms., acid content: 0.007, ester content: 3.56, alcohol content: 1.37) and frac- 14 tions 7-14 are combined (144.5 gms., acid content: 0.008, ester content: 4.08, alcohol content: 1.31).

The foregoing material is representative of esters obtained by reacting a ratio of moles of alcohol to equivalents of lactic acid. The low-boiling section is very good in improving the taste and sidestream aroma of stems, black tobacco, and reconstituted tobacco sheet. The highboiling section is very good in smoothing out the harshness of heavy, harsh cigarette tobaccos and in enhancing the flavor of mild and low-grade tobaccos.

EXAMPLE XIV A mixture of 239 gms. isoprenoid ester residue (acid content: 0.015, ester content: 1.19, alcohol content: 0.104), 227.2 gms. ethyl lactate, 22.7 gms. sodium methylate, and 1250 gms. n-hexane is heated at 70 to 72 C. and the methanol-, ethanol-, and ethyl acetate-hexane azeotropes distilled olf over a period of nine hours. The reaction mass is then cooled, acidified with acetic acid, and Washed to neutrality with water and dilute sodium bicarbonate. The hexane is recovered under vacuum.

About 255 gms. of crude is obtained (acid content: 0.02, ester content: 2.61, alcohol content: 0.87) and 240 gms. of this is distilled under reduced pressure. 160 gms. of product is obtained. The fractions obtained at the following rotor temperatures test as shown below:

Fraction Acid Ester Alcohol Rotor Pressure, number content content content temp. microns Nil 2. 91 0. 72 64 32 Nil 2. 59 0. 63 67 15 Nil 2. 37 0. 60 79 10 Nil 2. 44 0. 69 8 Nil 2. 56 0. 72 6 Nil 2. 71 0. 73 111 6 Fractions l-7 are combined (140.5 gms., acid content: 0.004, ester content: 0.12, alcohol content: 0.11), and fractions 8-15 were combined (130.2 gms., acid content: 0.01, ester content: 0.49, alcohol content: 0.09).

The material of this example improves the flavor of various cigarette tobaccos.

EXAMPLE XV I Preparation of lactic acid ester of geraniolnerol mixture A mixture of 118.2 gms. of mixed 60-40 geraniolnerol, 795.0 gms. ethyl lactate, 11.8 gms. sodium methylate and 2000 ml. of toluene is heated and the methanol/ethanoltoluene azeotropes distilled on for a period of 10 hours. The reaction mass is then cooled, acidified with acetic acid, and washed to neutrality with water and dilute sodium bicarbonate solution.

The toluene is removed under vacuum, and 462 gms. of crude is obtained (ester content: 9.23, alcohol content: 2.99). Then 440.0 gms. of crude is distilled under reduced pressure to obtain 349.5 gms. of product. The fractions, obtained at the indicated rotor temperatures, test as shown below:

Fraction Ester Alcohol Rotor Vacuum, number content content temp., 0. microns Fractions 1-6 are combined (165.0 gms., ester content: 8.15, alcohol content: 4.03), and fractions 7-13 are combined (173.0 gms., ester content: 9.29, alcohol content: 3.01).

EXAMPLE XVI Preparation of lactic acid ester of terpineol A mixture of 118.0 gms. of tat-terpineol, 795.0 gms. ethyl lactate, 11.8 gms. sodium methylate and 2000 ml.

of toluene is heated and the methanol/ethanol-toluene azeotrope distilled oif for a period of 12 hours. The reaction mass is then cooled, acidified with acetic acid, and washed to neutrality with water and dilute sodium bicarbonate solution. The toluene is removed under vacuum to obtain 500 gms. of crude (ester content: 9.37, alcohol content: 1.61).

Then 475 gms. of crude is distilled under reduced pressure to obtain 291.0 gms. of product. The fractions, obtained at the indicated rotor temperatures, test as shown below:

Fraction Ester Alcohol Rotor Vacuum, number content content temp., 0. microns Fractions 1-5 are combined (133.0 gms., ester content: 8.53, alcohol content: 2.49), and fractions 6-11 are combined (158.0 gms., ester content: 11.84, alcohol content: 2.29).

EXAMPLE XVII Preparation of lactic acid ester of nerolidol A mixture of 166.0 gms. of nerolidol, 795 gms. ethyl lactate, 16.6 gms. sodium methylate and 2000 ml. of toluene is heated and the methanol/ethanol-toluene azeotropes distilled off for a period of 5 hours. The reaction mass is then cooled, acidified with acetic acid, and washed to neutrality with Water and dilute sodium bicarbonate solution. The toluene is removed under vacuum to obtain 468 gms. of crude (ester content: 7.66, alcohol content: 1.81).

Then 450 gms. of crude is distilled under reduced pressure to obtain 332 gms. of product. The fractions, obtained at the indicated rotor temperatures, test as shown below:

Fraction Ester Alcohol Rotor Vacuum, number content content temp., 0. microns Fractions 1-6 are combined (143.0 gms., ester content: 3.89, alcohol content: 1.87) and fractions 7-13 are combined (189.0 gms., ester content: 8.42, alcohol content: 2.01).

EXAMPLE XVIII Evaluation of lactic acid esters of terpene and sesquiterpene alcohols The terpene and sesquiterpene esters prepared as fractions 16 of Example XV, 1-5 of Example XVI, and 16 of Example XVII are evaluated as follows:

Each ester is dissolved in about 10-15 times its weight of ethyl alcohol and sprayed on samples of a cut rag-form blend of 45% burley-55% Virginia tobacco in an amount suflicient to provide 1% of the ester on the tobacco. The tobacco is air-dried to remove the bulk of the alcohol and made into cigarettes. The cigarettes are then conditioned for a day to ensure complete removal of the alcohol and to blend the flavor.

The lactic acid ester of the geraniol-nerol mixture prepared in Example XV reduces the dirty, woody notes associated with the strong blend of burley and Virginia tobaccos. The lactic acid esters of terpineol and nerolidol prepared, respectively, in Examples XVI and XVII similarly reduce the dirt, woody notes of the burley-Virginia blend.

1 6 EXAMPLE XIX Preparation of lactic acid polymer A mixture of 1000 gms. of ethyl lactate, 100 gms. sodium methylate, and 5000 gms. of toluene is heated for 12 hours and the toluenemethanol/ethanol azeotropes are distilled 011. The reaction mass is then cooled, acidi-' fied with acetic acid, and washed to neutrality with water and dilute sodium bicarbonate solution.

The toluene is recovered from the washed reaction mass under vacuum to obtain 470 gms. of crude product. The crude material is distilled under a reduced pressure of 125-180 microns Hg to obtain 128 gms. of material. The fractions, obtained at the indicated rotor temperatures, test as shown below:

with strong burley-Virginia mixtures such as described above.

While the foregoing preparation shows the ester produced by the reaction of ethyl lactate, the lactic acid polymer can also be prepared directly from lactic acid.

EXAMPLE XX Evaluation of polylactic acid-containing mixtures A -50 mixture of the lactic acid polymer made in Example XIX and the lactic acid ester of isoprenoid alcohol made in Example XII is prepared and dissolved in ethyl alcohol, applied to a burley-Virginia blend of to bacco, and tested as in Example XVIII. The combination produces a very desirable mild smoke.

EXAMPLE XXI Evaluation of combination of the lactates of isoprenoid alcohol and of nerol-geraniol A 5050 mixture of the lactate of isoprenoid alcohol of Example XII and of the lactate of the nerol-geraniol mixture of Example XV is prepared and evaluated on a burley-Virginia mixture as in Example XVIII above. This mixture is judged to confer a more natural flavor on the tobacco and to give a mild smoke.

EXAMPLE XXII Preparation of lactic acid polymer A mixture of 2,000 gms. of butyl lactate, 200 gms. of sodium methylate and 10,000 gms. of toluene is heated for 11 hours while the methanol/butanol-toluene azeotropes are distilled 01f. The reaction mass is then cooled, acidified with acetic acid, and washed to neutrality with Water and dilute sodium bicarbonate solution.

The toluene is recovered from the washed reaction mass under vacuum to'obtain 546 gms. of crude material having: acid content, 0.016; ester content, 9.68; alcohol content, 3.88. Thereupon, 536 gms. of crude isdi'stilled under reduced pressure to obtain 421.8 gms. of product.

The fraction noted below had the following characteristics:

Fraction Acid Ester Alcohol Rotor Vac number content content content temp., C mic i l i Nil 9. 13 4. 40 43 37 N 9. 28 4. 38 42 22 N11 8. 85 4. 38 48 17 N 1 9. 25 4. as 44 12 N11 9. s4 4. 24 47 12 N 1 9. 53 4. 12 54 12 N11 10. 10 3. 50 17. 0. 008 10. 30 3. 25 10 0. 020 10. 40 3. 15 8 Fraction Nos. l-9 are combined to provide 227.0 gms. of lactic acid polymer with acid content, nil; ester content, 9.43; alcohol content, 4.15 and fractions 10-19 are combined to provide 194.8 grns. of lactic acid polymer having acid content, 0.009; ester content, 9.93; alcohol content, 3.13.

This lactic acid polymer prepared from a butyl lactate has substantially the same smoking characteristics as that produced in Example XIX.

EXAMPLE XXIII Preparation of lactic acid polymer A mixture of 606 gms. of commercial lactic acid, 300 gms. of benzene, and 8.8 girls. of concentrated sulfuric acid is refluxed using a water separation trap until liberation of water ceases. The reaction mass is then cooled and 16.2 gms. of sodium acetate is added. The mass is agitated for 10 minutes, washed with water, and dried.

The solvent is recovered under reduced pressure and 323 gins. of the lactic acid polymer is obtained with acid content, 1.19; ester content, 12.6; alcohol content, 0.91.

The lactic acid polymer provided by the foregoing process increases the strength while reducing the harshness of the smoke. It is useful for most to'baccos.

What is claimed is:

.1. A tobacco product having improved flavor and smoking characteristics comprising tobacco and a small but effective amount by weight of a lactic acid ester of an isoprenoid alcohol.

2. The tobacco product of claim 1 wherein the ester contains at least one molecular proportion of lactic acid for each molecular proportion of isoprenoid alcohol.

3. The tobacco product of claim 1 wherein the ester contains from about 3 to about molecular proportions of lactic acid for each molecular proportion of isoprenoid alcohol.

4. The tobacco product of claim 1 wherein the isoprenoid alcohol is a terpene alcohol.

5. The tobacco product of claim 1 wherein the isoprenoid alcohol is a sesquiterpene alcohol.

6. The tobacco product of claim 1 wherein the isoprenoid alcohol is an alcohol prepared by polymerizing isoprene.

7. The tobacco product of claim 6 wherein the ester has an acid content of from nil to about 0.045, an alcohol content of from about 0.4 to about 2.5, and an ester content of from about 0.3 toabout 7.5.

8. The tobacco product of claim 6 wherein a lactic acid polymer is also present.

9. The tobacco product of claim 1 wherein the ester contains about 9 molecular proportions of lactic acid for each molecular proportion of isoprenoid alcohol.

10. The tobacco product of claim 1 wherein the ester is present in an amount from about 0.05 percent to about 5.0 percent by weight of the tobacco product.

References Cited UNITED STATES PATENTS 70,386 11/1867 Arnd 131-17 2,312,685 3/1943 Borglin 260-489 3,023,183 2/1962 Nelson 260-484 X 3,139,888 7/1964 Grossman et al. 13117 3,278,589 10/1966 Scriabine 260-489 3,294,837 '12/1966 Thompson 260-484 3,306,303 2/1967 Bauley et al. 131-17 OTHER REFERENCES Grunwald, Chem. Ab., vol. 53: 22, 770(a) (1959).

Quin et al., Chem. Ab., vol. 55: 18,021(f) (1961).

Rowland et al., J. Am. Chem. Soc., vol. 78, pp. 4680- 4683 (1956).

Rowland et al., Tobacco Science, vol. IV, pp. 29-32 (1960).

Wagner et al., Synthetic Organic Chemistry, p. 486 (1953).

MELVIN D. REIN, Primary Examiner.

U.S. DEPARTMENT OF COMMERCE PATENT OFFICE Washington, 0.0. 20231 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,402 ,721 September 24 1968 Ernst T. Theimer et al.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 39, "methenyl" should read menthenyl Column 12, line 35, "44-55" should read 45-55 line 64, "temperatures" should read temperature Column 13 second table, first column, lines 3 to 6 thereof, "1", "l", "60", and "82" should read 6 8 l0 and l2 Column 15, line 74, "dirt" should read dirty Signed and sealed this 10th day of February 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Attesting Officer Commissioner of Patents WILLIAM E. SCHUYLER, JR. 

1. A TOBACCO PRODUCT HAVING IMPROVED FLAVOR AND SMOKING CHARACTERISTICS COMPRISING TOBACCO AND A SMALL BUT EFFECTIVE AMOUNT BY WEIGHT OF A LACTIC ACID ESTER OF AN ISOPRENOID ALCOHOL. 